[URL="http://api.tweetmeme.com/share?url=http://espn.go.com/nfl/story/_/id/8432605/rams-running-back-steven-jackson-misses-practice&service=bit.ly&source=espn"][IMG]http://api.tweetmeme.com/imagebutton.gif?url=http://espn.go.com/nfl/story/_/id/8432605/rams-running-back-steven-jackson-misses-practice[/IMG][/URL]While Steven Jackson saves himself for Sunday, his rookie understudies are getting more shots to prove they belong.